Swamp eels emerging as pest in rice farms
SCIENCE CITY OF MUÑOZ—Rice farmers in some parts of Nueva Ecija and two other provinces have reported that swamp eels have appeared in their farms and damaged their irrigation dikes.
As predators, the eels also pose threat to other fish, amphibians and aquatic invertebrates, researchers of the Philippine Rice Research Institute (PhilRice) here said.
Leonardo Marquez, science research analyst of PhilRice’s crop protection division, said reports about the presence of the eels in farms came out only this cropping season when his group visited Barangay Maragol here.
“Several farmers there reported several hundred or even thousands [of eels in their farms],” Marquez said.
Other PhilRice stations also reported the presence of eels in rice farms in Isabela and Negros Occidental, Marquez said.
Adriano Comilang Sr., a farmer in Maragol, said eels burrowed deep into the soil and destroyed his farm’s dikes.
As a result, the retention of irrigation water in the farm has become very poor due to seepage, Comilang said.
Marquez said that due to the seepage, farmers believe that nutrients from the fertilizers applied on their crops were washed out.
Marquez said water management for the growing rice plants has also been compromised due to the holes in the dikes.
“Farmers reported that it was difficult to determine where the seepage was coming from because they could not see the holes,” Marquez said.
Gregorio Gaspuz, another farmer in the village, told Marquez that he applied molluscides (pesticides against snails) but only about 20 eels were killed.
Gaspuz said farmers started noticing the eels in their farms two years ago. They tried catching and cooking them but they could not stand the taste.
“They are like small snakes seen in the paddy when we begin plowing the field,” Marquez quoted Gaspuz as saying.
Marquez said the eel was identified by a scientist from the Freshwater Aquaculture Center here as the Asian swamp eel (Monopterus albus). It is commonly called igat, palos or kiwit and grows up to 40 centimeters as an adult.
It burrows as deep as 1.5 meters during the dry season to survive dry conditions. A nocturnal fish, it feeds on fish, crustaceans and other invertebrates and normally found in rivers, lakes, ponds, marshes, swamps and drains.
